Deceleration control system



March 3, 1959 w. E. LE lBlNG ETAL DECELERATION CONTROL SYSTEM 3 Sheets-Sheet 1 Filed April 15, 1957 WILL/AM t. LE/Bl/VG i Graze: hf POWELL INVENTORS 1,71 r-rae/vm s March 3, 1959 w. E. LEIBING ETAL 2,875,741

DECELERATION CONTROL SYSTEM 3 Sheets-Sheet 2 Filed April 15, 1957 VV/LL/AM [LEE/N6 Graze: h. Pom ELL INVENTOR.

ATTORNEYS March 3, 1959 w. E. LElBlNG ET AL 2,875,741

DECELERATION CONTROL SYSTEM 3 Sheets-Sheet 5 Filed April 15, 1957 quail/ilk WILL/AM E LE/E/NG GEO/96E ff Pan :24

INVENTORS W m Arman-r5 DECELERATION CONTROL SYSTEM William EaL'eibing;RedwoodzCity,yand George H. Powell,Los Angeles, Calif.

Application April 15, 1957;"Serial No. 652,876 IS-Claims. (Gl.,,123-.-97') This invention relates rtodeceleration control systems.

duce ,air into appropriate -jetswof thecarburetor to reduce orblockflow of fuel therefrom into, :theintake manifold,

and alsotarrangedlto inject simultaneously agquantity of air directly intothedntake manifold calculated to*compensate for the, excesstor wettuel;which wouldlotherwise existtherein during deceleration.

Third, to provide a fuel control system of, this type which also effects shut-off of the main fuel supply during deceleration, so that in the event of prolongeddeceleration, or a prolongedperiod whentthe engine is operating in compression-as for example-when driving down grade-the fuel is not wasted orpermitted to accumulate in the intakecor exhaust manifolds; thus avoiding later obnoxious discharge of unburned fuel.

Fourth, to provideta deceleration fuel control system which is particularly applicable to engines equipped with after burners or other devices associatedlwith theengine exhaust for controllingthe discharge of smog-producing chemicals.

With the above and other objectstin view, as may appear hereinafter, referenceis directed .to'the accompanying drawings in which:

Figure 1 is a schematic view of the deceleration control system showing one improvement thereover, with portions in elevation and other portions in section;

Fig. 2 is a similarschematic view showing a modified form of the deceleration control system;

Fig. 3 is an end view of a modified form ofthe throttle delay unit;

Fig. 4 is a longitudinal sectional view thereof.

Reference is first directed to Fig, 1. The deceleration control system is adapted to be installed on motor vehicles having carburetor-controlled engines,

The carburetor, designated 1, i's conventional and is shown in simplified outline form. The carburetor ineludes an air intake 2, afuel inlet 3, and is provided with a throat 4 which communicates with an intake manifold 5.

of a vehicle. The throat 4 is intersected by an idling jet orifice 9 having a screw adjustment 10 and supplied through a fueltduct 11..

The deceleration control. system utilizes a throttle delay nitedStates Patent 0 2; unit,- designated A," which 'is mounted at one :side rof the carburetor throat 4.: The unit includes a pair of housingmembers 12'and 13.- One 'ofthe housing members-is provided with anexternally screw-threaded sleeve 14- which serves to mount the housing'memberon a bracket 15,

The "housing members 12 and 13 are complementaryand clamp therebetween a diaphragm" 16 towhi'clt is attached 'a stem' 17 slidably mounted innthe sleeve 14: The extended end of the stem 17 is provided with "ahead" 18 iwhich is engaged by an operating screw. l9 adjustably mounted ontheoperat-ing'arm 8 of the-earburetor throttle valve.

The housing m'ember' 13 isprovided "with ia hollbw stem' 20 coaxia1 with the stem :17 and in which ismounted a :spring 21,: which engages the diaphragm '16 and urges the stem 17 tinto engagem'ent with theoperating screw-19."-

The extremity of the hollow stem 20 is provided with an external flangez 22 over which is fitted a -flanged cap' 23.. Clamped between the cap 23 and: flange 22' -is' a switch t diaphragm: 24. Mounted in the :cap is an insu lated teminal 25 which isrengageable by a contactbutton 26 carried by the diaphragm 24. A spring 27 forms-am grounding contact for the :button 26 and also urges the buttoni26'vaway from the terminal 25.

The interiorof 1 the housing member 13 and its hollow stem i=20wbetween theadiaphragms 16and 24 forms: a time delay 'chamber. 28. A [check valve 29 permits ready entrance of'air .to. thischamber' so that the stem' 17- -'is free'to moveaoutwardly andfmaintaincontact with thezoperating SCIBW I9;

A meteringtport 30 restricts escape of air from the chamber 28 so 'thatumovem'ent of. the throttle valvew6 towards its: closed position is delayed by the rate-of "fair escaping, throughthe metering port 30. In order to predetermine :accurately t-the' efiective area of the :metering port, a meteringwire 31 is threaded through th'e port 30 andwits ends bent over to retain the -wirein pla'ce.'

The deceleration control a system also includes: a cluster valve structure which comprises integrallyconnected valve units, namely: an air supply valve unit B,T a regulator valve Unit C, and a fuel: shut-off valve unit D; These unitsnare, in: actual practice, grouped about a common center,1 but: forcconvenience ofrillustration .they have been. shown as arranged with-their axes in a common plane. The: valve units thus share a common valve body 32 and a common cap structure 33;

The airsupply valvewunitvB iscprovided withan-airreceivingnchamber 34 having a lateral inlet port'35 which is preferably connected tothe air cleaner of theengin'e,

,not'shown. The air-receiving chamber 34 is provided with a coaxialamanifold "air supply valve port 36 and a carburetor idler jet air supply port 37, which 'are co'ntrolledrespectively by a manifold supply valve '38 and an tidlerjet' supply valve39.: The valves 38 land 39 are connected by a stem 40 so that the valvesmay move'in unison. A solenoid armature 41 is operatively joined to the stem .40.-

A -solenoid42 receives the armature'41 andis.pro-; videdwith a case which capsthe'air-receiving chamber 34. Theisolenoid 42 iseonnected through a relay switch 43and preferably through a thermostat 'switeh 44tozthez terminal 25 so that upon closing of the terminal 25-L'thez. air: supplyvalve unitiB opens, assuming that the "engine temperature predetermined by the thermostat switch'"44 is adequate.

The manifold air supply valveport 36 communicates with a manifold supply chamber 45 which in turn is con nected. to a manifold air supply line 46 leading from the" chamber 45 to the intake manifold 5. An idler iet' air 1ine-47leads'from-the idlerjet -airsupply port37 'tdth'e' 3 fuel supply duct 11 of the carburetor at a point adjacent the idler jet 9.

The regulator valve unit C includes a diaphragm 48 clamped between the valve body 32 and cap structure 33. The diaphragm 48 forms with the cap structure 33 a manifold pressure chamber 49 which is maintained in communication with the intake manifold 5. This may be done by a passage 50 communicating with the manifold supply chamber 45 and the manifold air line 46.

The diaphragm 48 forms with the valve body 32 an atmosphere chamber 51 communicating with the surrounding atmosphere through a port 52 so that the underside of the diaphragm 48 is at all times subjected to atmospheric pressure.

-The diaphragm 48 supports a needle valve 53 which extends downwardly into a bore 54 formed in the valve body 32. The needle valve controls flow through a manifold pressure duct 55. One end of the duct 55 is maintained in communication with the manifold so as to reflect the pressures existing therein. This may be done by communication through the manifold supply chamber 45 and manifold air line 46. The other end of the duct 55 communicates with the fuel shut-ofi valve D to be described hereinafter. The needle valve 53 is urged towards a closed position by a spring 56 located above the diaphragm 48. The force of the spring 56 may be adjusted by a set screw 57. r

' The fuel shut-off valve D includes a diaphragm 58 which is also clamped between the valve body 32 and cap structure 33. The diaphragm 58 defines with the cap structure33 a manifold pressure chamber 59 which is in communication with the manifold pressure duct 55.

Secured in the valve body 32 under the diaphragm 58 isa fuel diaphragm '60 which forms with the diaphragm 58 and the valve body an atmosphere chamber 61 in communication with the surrounding atmosphere through a port 62. The underside of the diaphragm 60 forms with thevalve body 32 a fuel chamber 63 which is connected through a fuel outlet port 64 with the fuel inlet 3 of the carburetor 1. The valve body 32 projects below the fuel chamber 63 to form a fuel inlet chamber 65.

Between the fuel chamber 63 and fuel inlet chamber 65 there is formed a perforated partition, at the underside of which is provided a fuel inlet valve seat 66. The valve seat 66 is engageable by a slidable fuel valve 67 movable axially in the inlet chamber 65. The open lower end of the inlet chamber 65 receives a plug 68 having a screw-threaded bore therein for connection to a fuel supply line, not shown. A spring 69 is interposed between the'plug 68 and valve 67 to urge the valve towards its seat 66. A stem 70 extends between the valve 67 and the diaphragm 60' so that when the diaphragm 60 is in a. lower position the fuel valve 67 is open, and when the diaphragm 60 is raised the fuel valve is closed.

Carried by the underside of the diaphragm 58 is a force-transmitting button 71 which is engaged by the diaphragm 60. Also carried by the diaphragm 58 on its upper side is a contact button 72. The contact button 72 is adapted to engage an insulated terminal 73 secured in the cap structure 33. A spring 74 provides grounding contact for the button 72 and normally holds the button clear of the terminal 73. The terminal 73 is electrically'connected to the relay 43 through the thermostat switch'44. Thus the switch formed by the terminal 73 andcontact button 72 is electrically in parallel with the switch'formed by the terminal and contact button 26.1 a a Operation of the deceleration control system is as follows:

The throttle delay unit A and the various valve'units B, C, and'D are shown in Fig. 1 in the condition assumed when the engine is not in operation. When the engine is running under power the throttle valve 6 is open so that the stem 17 occupies a position to the right of that shown in Fig.1. Underthis condition the manifold pre's- 4 sure is relatively high so that the air supply valve unit B is closed, the regulator valve unit C is closed, and the fuel shut-off valve D is open, these valve units being in the position shown in Fig. 1.

When it is desired to decelerate the engine, the operator removes his foot from the accelerator pedal connecting with the operating arm 8 of the throttle valve 6, permitting the operating arm under urge of a spring, not shown, to move clockwise toward the position shown in Fig. 1. This clockwise movement moves the throttle valve 6 towards its closed position. The rate at which the throttle valve may close is determined by the throttle delay unit A, that is, by the rate of discharge of air through the metering port 30. As a consequence, air pressure is built up sufiiciently in the chamber 28 to move the switch diaphragm 24 to the left, closing the switch formed by the terminal 25 and contact button 26.

If the thermostat switch 44 is closed, the relay 43 is energized to activate the solenoid'42. This opens simultaneously the manifold air supply valve port 36 and the idler jet air supply port 37.

Closing movement of the throttle valve 6 increases the vacuum or suction pressure in the intake manifold 5 so that on opening of the air supply valve unit B air is drawn through the air line 47 to the fuel supply duct 11. This air discharges through the idling jet 9 and partially or completely blocks the flow of fuel therethrough. At the same time air is drawn through the manifold air line 46 to the intake manifold 5. This operation takes place relatively rapidly, and in fact tends to anticipate the condition which would otherwise develop in the engine.

That is, without the deceleration control system the conventional carburetor-controlled engine will collect an excess amount of fuel in the intake manifold. Because the fuel is in excess, it is only partially burned as it passes through the combustion chambers of the engine. The remaining unburned fuel then passes from the engine to the exhaust manifold and to the atmosphere.

It should be noted that one of the major sources of the air pollution commonly called smog is the result of the discharge of unburned fuel vapors, such as gasoline vapors, into the air. It has been fairly well established that these vapors react in the presence of sunlight to form the end product known as smog.

It should also be observed that serious attempts are being made to eliminate the discharge of unburned fuel from automobile engines by the provision of after burners or other devices in the exhaust system of the automobile. Such devices are capable of handling the relatively small amounts of unburned fuel that occur under normal operation of motor vehicles, but the excess of unburned fuel produced during deceleration places a severe burden on such devices. Therefore, by delaying the deceleration rate of the throttle valve and utilizing this movement to operate a valve for supplying air to the manifold as well as the idler jets of the carburetor, the presence of such unburned fuel is eliminated or materially reduced.

The description of the operation of the deceleration control system has, to this point, been concerned with the condition of momentary deceleration, as, for example, when a vehicle is being brought to a stop, as frequently occurs in driving in trafiic-controlled city streets.

Under conditions of prolonged deceleration, as, for example, when the vehicle is descending a grade under compression, movement of the throttle delay unit A is no longer available to actuate the air supply valve unit B. However, the need to prevent the accumulation of excess fuel in the intake manifold continues to exist. Thus, under conditions of prolonged deceleration the throttle valve 6 and the throttle delay unit A are in the position shown in Fig. l.

However, a vacuum exists in the intake manifold 5. This vacuum or suction pressure is transmitted to the top side of the diaphragm 48 of the regular valve unit C1. The suction pressure causes the diaphragm 48 to raise,

opening the needle valve 43,. which then permits: applicaonaofsthe suction pressure by reason of the duct .55 togthermanifold pressure chamber 59 at the upper side of thediaphragm 58. This causes the switch formed by the terminal 73 andcontact button.72 to close, and thus energizesthesolenoid. .42. andopens the air supply valve unit B.. Actually, however, the switch formed by the terminal 73 ;and contact 72closes before the switch formed by the terminal 25 and contact button 26 opens. Thus; the switch withinathe fuel shut-off valve D functions. before the momentary deceleration period ends.

Upward.movement,of the. diaphragm 58 also permits upwardmovement of the diaphragm 60 under urge of.

the spring 69 shutting off the fuel supply tothe carburetor, with the result that continued operation ofthe engine undercompression doesnot continue to drawfuel into the. take manifold; and thusthedischarge of unburned fuel s;prevented.

Immediately upon ,resuming a propulsion condition, in which the engine is brought into operation to drive themotor vehicle, the operator moves the throttle from its closedposition to an open or some intermediate position, causing an immediate reduction in the suction pressure within the manifold which is reflected in the pressures within themanifold pressure chambers 49. and 59. Also thestem ,17 immediately moves to the right, as viewed in Fig, 1, so that the spring 21 moves the diaphragm 16 to relievehany pressureinthe chamber 28 Thus both switches which control the solenoid are immediately opened, the air supply is cut off, and normal operation of the carburetorisimmediately resumed.

lt shouldbenobserved that the spring 56 of the regulatonyalveunitC. is so adjusted that a somewhat higher vacuum pressure is required to open the regulator valve unit Crthannor mally exists in the intake manifold during.

theinitial period. of deceleration, so thatnormally the regulator valve unit C does not function during momentary deceleration. 7 Furthermore, the atmosphere port 52 in the regulator valveunit C may be suflicient-ly small to delay closingaofthe regulatorvalve unit C to permit bleeding of pressure. into the manifold pressure chamber 59v atth. termination, of the deceleration period which has been prolonged to the point that the fuel shut-off valvepnit Dhas been operated.

Reference is now directed to Fig. 2. The function and operation of thedecclerationcontrol system shown in Fig. 2 is essentially the same as that described in Fig. 1. The essential difference lies in the utilization of vacuum pressure to operate the air supply valve unit B. For this purpose a modified throttle delay unit A1 is substituted for the throttle delay unit A, a modified air supply valve unit B1. is substituted for the air supply valve B, and a modified fuel shut-off valve unit D1 is substituted for the fuel shut-01f valve unit D.

The throttle .delay unit A1 utilizes the. housing members 12 and 13 of the first described structure. In place of the cap 23 there is provided a valve housing 75 which coactswith the flange 22 to clamp a diaphragm 76. The valve housing 75 is provided with a valve chamber 77 which communicates with a manifold pressure line 78 suitably connected to the manifold or to the manifold air line 46.

Within thevalve chamber 77 is .a needle. valve 79 which engages a valve seat 80. cates withthe valve seat 80 and with a control line 82. A small stem83 extends from the needle valve 79 to the diaphragm 76. so that movement of the diaphragm 76, by reason of pressure in the time delay chamber 28, will open the needle valve A spring 34 urges the needle valve. .79 towards its closed position.

Theair supply valve unit B1 is modified by substituting a diaphragm 85 for the solenoid valve and providing an extension 33a of the cap structure 33 which forms with the diaphragm 85 a manifold pressure chamber 86. The diaphragm.;85 is operatively; connected with the manifold A duct 81 oommuni 6. supply valve 38-and icll'en jet 'supply-valve 39-50 that-movement of the diaphragm will effe'ct simultaneous movement of these two valves. A-spring 87 bears against the diaphragm to 'urge the valves 38 and 39-toward their.

closed position. The control line 82 communicates; with the manifold pressure chamber 86.

The fuel shut-01f valve unit D1 is modified by 0mitting the terminal 73" and providing a branch 88 of the control line 82 'wliich'comm-unicates withthe'manifold pressure chamber 59w As indicated previously, the operationof the construction shown in Fig. 2 is essentiallythe same as thatshown in F ig. 1. During momentary decelerat-ionthe needle valve 79 is opened-by movement of the diaphragm76, which causesthe air supply valveunit B1toopen as in the case of the first described structure; Prolonged "deceleration causes the regulator valve unit C-l'to'opemwhich in turn causes the fuel shut-off valve unit D110 close as in the first described structure, and in so doing maintaining communication of the manifold pressure chamber 86 with the vacuumpressure -i'n theintake manifold so that the.

air supply valve unit B1 is maintained in open position. On resumption of normal or low-suction pressures in the intake manifoldythe increased pressure is reflected in the valve manifold pressure chambers so that the air supply This structure includes a mounting bracket 89 having.

a sleeve 90in which is slidably mounted a stem 91', the extremity of which is provided with a head 92'engageable by the operating screw 19,shown in the first vdescribed structure'. The stem 91 is preferably enclosed in a flexible boot 93 and is urged towards its extended position by a spring 94.

Secured to the bracket 89.-is a body structure 95' provided with a cylinder 96 coaxial with the stem 91. The cylinder receives a piston 97 secured to the inner end of the stem 91.= The piston is provided with portstherethrough which are controlled by a check valve .98-disposedon theside ofthe piston 97 opposite fromthe stem 91. The check valve 98-is provided Witha central stem 99 which extends into a socket provided in the stem 91 and connected to a spring 100 which urges the check valve 98 to its closed position.

The end of'the cylinder 96 opposite from the bracket 89 is closed by a cap 101' which serves to clamp a diaphragm 102-over this end ofthe cylinder. The cap 101 is provided with an insulated terminal 103 which is engaged. by a contact button 104 carried by the diaphragm 102. A spring 105 serves to ground the contact button 104 and to normally separate the contact button from the terminal;

Formed at the upper side of the cylinder 96- is a reser* voir 107 which is closed by a filler cap-108. A small passage 109leads fromthe cylinder 96" between the diaphragm 102 and piston 97 and communicates with the reservoir 107. This passage is controlled by a needle valve 110. An equalizer passage 111 communicates from the reservoir-107 to the back orstem side of the piston 97; Also ports 112 communicate between this side of the piston and theinterior of the boot 93. The interior of the boot 93', the cylinder 96, and the reservoir 107 are filled with a liquid, such as hydraulic fluid.

As in the first described throttle delay units A and A1, movement of the stem-91 to the left 'as viewed in Fig. 4 creates a pressure in the cylinder 96 sufiicient to close the switch by the terminal-103 and contact button 104. The pressure, however, 'is relieved at a controlled rate by flow of liquid from the cylinder-96' through: the needle valve 110 to the reservoir 107 so that the switch is not maintained closed unless there is continued movement to the left of the stem 91. The return movement of the stem is unimpeded, as the fluid may pass readily from the right to the left side of the piston 97 through the check valve 98.

It should be observed that the valve housing 75 of the modified throttle delay unit A1 with its needle valve 79 may be substituted for the switch represented by the terminal 103 and contact button 104 so that the throttle delay unit A2 may be modified for operation withthe structure shown in Fig. -2.

While particular embodiments of this invention have been shown and described, it is not intended to limit the same to the exact details of the constructions set forth, and it embraces such changes, modifications, and equivalents of the parts and their formation and arrangement as come within the purview of the appended claims.

What is claimed is:

l. A deceleration control system for an engine having a carburetor including a throttle valve and an intake manifold for receiving an air-fuel mixture from said carburetor, said control system comprising: an air supply valve bypassing said carburetor and connected with said intake manifold; means for predetermining the closing rate of said throttle valve; and means operatively connecting said air supply valve and predetermining means in response to closing movement of said throttle valve, to supply air through said air supply valve to said intake manifold during closing movement of said throttle valve.

2. A deceleration control system as set forth in claim 1, wherein: said predetermining means is an air-regulated dashpot.

3. A deceleration control system as set forth in claim 1, wherein: said predetermining means is a liquid-regulated dashpot.

4. A deceleration control system as set forth in claim 1, wherein: said air supply valve is a solenoid-operated valve, and said operatively connecting means includes a switch actuated by said predetermining means.

5. A deceleration control system as set forth in claim 1, wherein: said air supply valve is a diaphragm-operated valve, and said operatively connecting means includes a valve element for exposing said diaphragm to a motivating fluid.

6. A deceleration control system for an engine having a carburetor including a throttle valve and an intake manifold for receiving an air-fuel mixture from said carburetor, said control system comprising: an air supply valve by-passing said carburetor and connected with said intake manifold; means for predetermining the closing rate of said throttle valve; means operatively connecting said air supply valve and predetermining means in response to closing movement of said throttle valve, to supply air through said air supply valve to said intake manifold during closing movement of said throttle valve; a fuel supply valve for said carburetor, including means responsive to a predetermined high suction condition in said intake manifold for closing the supply of fuel to said carburetor; and means also responsive to said high suction condition to open said air supply valve whereby, when said fuel supply valve is closed, said air supply valve is open.

7. A deceleration control system for an engine having a carburetor including a throttle valve and an intake manifold for receiving an air-fuel mixture from said carburetor, said control system comprising: an air supply valve by passing said carburetor and connected with said intake manifold; and control means connected with said throttle valve and operative only during closing movement thereof from at least a partially open position to the closed position of said throttle valve, to cause flow of air from said air supply valve to said intake manifold while said throttle valve is in the act of closing.

8. A deceleration control system for an engine having 8 a carburetor including a throttle valve .and an intake manifold for receiving an air-fuel mixture from said carburetor, said control system comprising: an air supply valve by passing said carburetor and connected with said intake manifold; control means connected with saidthrottle valve and operative only during closing movement thereof, to cause flow of air from said air supply valve to said intake manifold; a fuel supply valve for said carburetor, including means responsive to a predetermined high suction condition in said intake manifold for closing the supply of fuel to said carburetor; and means also responsive to said high suction condition to open said air supply valve whereby, when said fuel supply valve is closed, said air supply valve is open.

9. A deceleration control system as set forth in claim 8, wherein: said air supply valve is a solenoid-operated valve and said control means connected with said throttlevalve, as well as the high suction responsive means connected with said fuel supply valve, include switches, each arranged to activate said solenoid.

10. A deceleration control system as set forth in claim 8, wherein: said air supply valve is a diaphragm-operated valve and said control means connected with the throttle valve includes a valve for applying manifold suction pressure to said diaphragm of the air supply valve thereby to open said air supply valve, said diaphragm of the air supply valve also being operatively connected with said fuel supply valve to open said air supply valve on closing of said fuel supply valve.

11. A deceleration control system for an engine having a carburetor including a throttle valve controlled throat and a fuel supply jet communicating with said throat, and an intake manifold for receiving a fuel-air mixture from said carburetor, said control system comprising: an air supply valve connected with said fuel supply jet and said intake manifold to supply air simultaneously thereto, thereby to render the carburetor substantially inoperative and deliver an auxiliary supply of air to said intake manifold; and control means connected with said throttle valve and arranged to open said air supply valve prior to complete closure of said throttle valve and maintain said air valve open during continued closing of said throttle valve.

12. A deceleration control system as set forth in claim 11, wherein: said control means connected with said throttle valve is an air-regulated dashpot.

13. A deceleration control system as set forth in claim 11, wherein: said control means connected with said throttle valve is a liquid-regulated dashpot.

14. A deceleration control system as set forth in claim 11, wherein: said air supply valve is a solenoid-operated valve and said control means connected with the throttle valve includes a switch for activating said solenoid during said closing movement of the throttle valve.

15. A deceleration control system as set forth in claim 11, wherein: said air supply valve is a diaphragm-operated valve and said control means connected with the throttle valve includes a valve element operative to expose said diaphragm to a motive fluid.

16. A deceleration control system for an engine having a carburetor including a throttle valve controlled throat and a fuel supply jet communicating with said throat, and an intake manifold for receiving a fuel-air mixture from said carburetor, said control system comprising: an air supply valve connected with said fuel supply jet and said intake manifold to supply air simultaneously thereto, thereby to render the carburetor substantially inoperative and deliver an auxiliary supply of air to said intake manifold; control means connected with said throttle valve and arranged to open said air supply valve prior to complete closure of said throttle valve and maintain said air valve open during continued closing of said throttle valve; a fuel supply valve for said carburetor, including means responsive to a predetermined high suction condition in said intake manifold for closingthe supply of fuel to said carburetor; and means also responsive to said high suction condition to open said air supply valve whereby, when said fuel supply valve is closed, said air supply valve is open.

17. A deceleration control means as set forth in claim 16, wherein: said air supply valve is a solenoid-operated valve and said control means connected with said throttle valve, as well as the high suction responsive means connected with said fuel supply valve, include switches, each arranged to activate said solenoid.

18. A deceleration control means as set forth in claim 16, wherein: said air supply valve is a diaphragm-oper- 10 ated valve, and said control means connected with the throttle valve includes a valve for applying manifold suction pressure to said diaphragm of the air supply valve thereby to open said air supply valve, said diaphragm of the air supply valve also being operatively connected with said fuel supply valve to open said air supply valve on closing of said fuel supply valve.

Hieger et a1 June 15, 1948 Heftler Jan. 11, 1955 

